FR2460529A1 - NEW EXCHANGE GROUPS FOR RADIOACTIVE SUBSTANCES STORAGE BASINS - Google Patents

Abstract

THE PRESENT INVENTION CONCERNS AUTONOMOUS EXCHANGE GROUPS FOR BASIN WATER FOR THE STORAGE OF RADIOACTIVE SUBSTANCES, CHARACTERIZED IN THAT THEY ARE IMMERED DIRECTLY INTO THE WATER OF THE BASIN AND THAT THE CIRCULATION OF THE WATER OF THE BASIN THROUGH THE DEVICE D 'EXCHANGE OF SUCH GROUPS IS CARRIED OUT BY KNOWN LOW OR MEDIUM PRESSURE DEVICES.

Description

The present invention relates to new exchange groups for basins.

Storage of radioactive substances. It is known that radioactive substances (for example waste or contaminated products) must be kept in tanks filled with water. The water in these basins must undergo

  exchanges which are either thermal exchanges or exchanges

ionic ages. Until now, these exchanges were carried out in exchangers located outside the basins, which required

the use of pumps to transport water from the basins.

It has been found and it is there the object of the present invention that it was desirable on the one hand that the exchanges are carried out in exchangers directly immersed in the water of the basins and on the other hand that said exchangers are a technology such as the circulation of water in basins,

  through these exchangers, it can be achieved using

positive at low or medium pressure.

The present invention therefore relates to autonomous exchange groups for water from radioactive substances storage basins, characterized in that said groups are immersed directly in the water of said basins and that the circulation of water from said basins through the device exchange of said groups is carried out by known devices at low or medium pressure. The invention will be better understood by referring to the single figure which represents, in section, the edge of a basin

  in which is immersed an exchange group according to the invention.

  In this figure we have schematized: - in 1 a vertical side wall, generally coated with stainless steel, of the basin, - in 2 the bottom of this basin also coated with stainless steel, - in 3 a base, rest on the bottom of the basin, capable of receiving the "exchange part" proper of the exchanger; this base is generally terminated at its upper part by a widening allowing easier installation of the exchange part proper; this base is preferably held at the bottom of the basin by a device with easy disassembly at a distance such as for example a bayonet device; finally, this base is provided with an opening allowing the water to exit from the bassi.n after it has passed through the exchanger,

- in 4 the "exchange part" proper, This part -

  is for example a tubular heat exchanger or an ion exchanger comprising one or more exchange beds in the single figure on.a diagrammatically shows a tubular heat exchanger. This "exchange part" 4 is set up on the

  base 3 thanks to its slightly conical low shape which corresponds to

lays at the base flare; the upper end of this exchange part is itself flared so as to receive the "chateau" of circulation. The cooling fluid is brought to this exchange part by means of tubes 5, preferably flexible and easily removable; this fluid can be, for example, unpolluted water, the circulation of which is ensured by a suitable submerged or non-submerged pump and the cooling of which. is provided by an exchanger (for example water / air) located outside the basin; in the figure there is shown schematically such a pump and such an exchanger but this fluid can also be a liquid

vaporizable as known.

  ) - in 6 the "castle". of basin water circulation; this castle comes to fit by a low conical part in the flare

  of the upper part of 4. This castle is essentially

  driven by a motor 7 located outside the basin which drives a propeller 8 which ensures the suction of the water from the basin through one or more openings 9 and the discharge of this

  water, through the exchange part 4, until the opening practi-

  quée in the base 3. It is possible to use other water circulation devices than that (motor-propeller) represented in the figure, it is however essential, in order to be able to benefit from all the advantages of the invention, that the "exchange part" causes only a small pressure drop in the water in the basin and therefore, it is possible to use "devices

circulation "type of low or medium pressure.

  The advantages of the new exchange groups immersed in the basins are numerous; we can cite for example: - the absence of circulation of polluted water from the basins outside these basins, - the fact that one does not have to use, to circulate the water of the basins, pumps, with cable gland and valves, S delivering water under high pressure, - the ease of assembly and disassembly of the exchange groups, the energy self-sufficiency that can be ensured, in some cases, by a recovery system of mechanical energy combined with

  pond water cooling system.

It is also possible according to the present invention to carry out, in the same exchanger, thermal and ionic exchanges which in particular makes it possible to carry out said exchanges

  ionic at a controlled and adequate temperature.

Claims (3)

-REVENDECAT ONS   1, Self-exchange groups for substance storage pond water. radioactive, because: ctérisés in that they are immersed directly in the water of said basins and that the circulation of water in said basins through the exchange device of said groups is effected by known devices at low or medium pressure. 2. Groups according to claim 1, characterized   in that there is heat and / or ion exchange. 3. Groups according to one of claims 1 and 2, characterized in that they are easily removable, by simple interlocking for example, so as to allow easy change of the actual exchange device.